/*
 * Copyright 2002-2019 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.hsc.lock.interceptor;

import org.springframework.lang.Nullable;
import org.springframework.util.Assert;

import java.io.Serializable;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.Collection;

/**
 * Composite {@link OperationSource} implementation that iterates
 * over a given array of {@code CacheOperationSource} instances.
 *
 * @author Costin Leau
 * @author Juergen Hoeller
 * @since 3.1
 */
@SuppressWarnings("serial")
public class CompositeLockOperationSource implements OperationSource, Serializable {

    private final OperationSource[] cacheOperationSources;


    /**
     * Create a new CompositeCacheOperationSource for the given sources.
     *
     * @param cacheOperationSources the CacheOperationSource instances to combine
     */
    public CompositeLockOperationSource(OperationSource... cacheOperationSources) {
        Assert.notEmpty(cacheOperationSources, "CacheOperationSource array must not be empty");
        this.cacheOperationSources = cacheOperationSources;
    }

    /**
     * Return the {@code CacheOperationSource} instances that this
     * {@code CompositeCacheOperationSource} combines.
     */
    public final OperationSource[] getCacheOperationSources() {
        return this.cacheOperationSources;
    }


    @Override
    public boolean isCandidateClass(Class<?> targetClass) {
        for (OperationSource source : this.cacheOperationSources) {
            if (source.isCandidateClass(targetClass)) {
                return true;
            }
        }
        return false;
    }

    @Override
    @Nullable
    public Collection<ReplayLockOperation> getCacheOperations(Method method, @Nullable Class<?> targetClass) {
        Collection<ReplayLockOperation> ops = null;
        for (OperationSource source : this.cacheOperationSources) {
            Collection<ReplayLockOperation> cacheOperations = source.getCacheOperations(method, targetClass);
            if (cacheOperations != null) {
                if (ops == null) {
                    ops = new ArrayList<>();
                }
                ops.addAll(cacheOperations);
            }
        }
        return ops;
    }

}
